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我在将以下几行翻译成 C# 时遇到问题：

extern leveldb_filterpolicy_t* leveldb_filterpolicy_create(
    void* state,
    void (*destructor)(void*),
    char* (*create_filter)(
        void*,
        const char* const* key_array, const size_t* key_length_array,
        int num_keys,
        size_t* filter_length),
    unsigned char (*key_may_match)(
        void*,
        const char* key, size_t length,
        const char* filter, size_t filter_length),
    const char* (*name)(void*));

这个函数是从本机 dll 导出的，我需要从 C# 调用它，我知道 , destructor, create_filter,key_may_match是nameC# 中的代表，但是const char* const*类型让我偶然发现它在 C# 中的外观，我的主要问题是是否可以编组这些通过 MarshalAs 属性使用标准方法的值，

顺便说一句，我对更简单的构造没有任何问题，例如：

public class Driver
{
    static void Validate(string error)
    {
        if (!String.IsNullOrEmpty(error))
        {
            throw new ApplicationException(error);
        }
    }

    public static extern leveldb_t leveldb_open(leveldb_options_t options, [param: MarshalAs(UnmanagedType.LPStr)] String name, out string error);
    public static extern void leveldb_close(leveldb_t db);
    public static extern void leveldb_put(leveldb_t db, leveldb_writeoptions_t options, byte[] key, size_t keylen, byte[] val, size_t vallen, out string error);
    public static extern void leveldb_delete(leveldb_t db, leveldb_writeoptions_t options, byte[] key, size_t keylen, out string error);
    public static extern void leveldb_write(leveldb_t db, leveldb_writeoptions_t options, leveldb_writebatch_t batch, out string error);

    // Returns NULL if not found.  A malloc()ed array otherwise. Stores the length of the array in *vallen.
    [return: MarshalAs(UnmanagedType.LPArray, SizeParamIndex=4)]
    public static extern byte[] leveldb_get(leveldb_t db, leveldb_readoptions_t options, byte[] key, size_t keylen, out size_t vallen, out string error);
    public static extern leveldb_iterator_t leveldb_create_iterator(leveldb_t db, leveldb_readoptions_t options);
    public static extern leveldb_snapshot_t leveldb_create_snapshot(leveldb_t db);
    public static extern void leveldb_release_snapshot(leveldb_t db, leveldb_snapshot_t snapshot);

    [return: MarshalAs(UnmanagedType.LPStr)] 
    public static extern String leveldb_property_value(leveldb_t db, [param: MarshalAs(UnmanagedType.LPStr)] String propname); // Returns NULL if property name is unknown. Else returns a pointer to a malloc()-ed null-terminated value.

    ...
}
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